16. In order to remove internal stresses produced by hardening the steel, the process usually adopted is-
A. spheroidising
B. annealing
C. normalizing
D. tempering
17. In block brakes, the ratio of shoe width to wheel diameter is taken between-
A. 0.1 and 0.25
B. 0.25 and 0.50
C. 0.50 and 0.75
D. 0.75 and 1
18. When a machine member is subjected to torsion, the torsional shear stress set up in the member is-
A. maximum at the centroidal axis and zero at the outer surface of the member
B. maximum at both the centroidal axis and outer surface of the member
C. zero at both the centroidal axis and outer surface of the member
D. zero at the centroidal axis and maximum at the outer surface of the member
19. The dedendum is the radial distance from the-
A. pitch circle to the top of a tooth
B. addendum circle to the clearance circle
C. pitch circle to the bottom of a tooth
D. top of a tooth to the bottom of a tooth
20. Two shafts of the same length and material are joined in series. If the ratio of their diameters is 2, then the ratio of their angles of twist will be-
A. 3
B. 6
C. 8
D. 16